Fluance RT85 headshell/overhang distance

[preacherJohn]

I'm looking for the distance of the Fluance RT-85 overhang on the headshell between the stylus and the rubber washer at the rear of the headshell connector. Fluance provides overhang data as 19.2 mm, but the distance of the MP110 is way further than that. My Denon's measurement was 49mm, and my Pioneer is 51mm. I was setting up a Grado pretige red on another cart, and I measured the Nagaoka that the RT-85 came with (it slips my mind what the number was), and used that with the Grado and new headshell. Of course I used a protractor, and all looks well, but I'm curious as to what Fluance uses as the 19.2 would not be correct with that type of measurement from stylus to rear of headshell connector. It was pretty large even more than the Pioneer's PL518. Thanks for you wisdom.

 

[Powertech]

Looking around, there seems to be little information on this. Fluance suggest checking with an alignment protractor. They provide a printable version which looks like a standard Baerwald 1 alignment It looks like you ignore the actual stated overhang and use the alignment protractor.

 

[charles 1973]

I believe the 19.2mm overhang refers to the distance between the calibration line marked on the protractor to the stylus tip when the line marked "line up with tonearm pivot" is in position That's how it works with the Rega Planar Two I bought last year.

The dimension you are referring to sounds like one used on my old Realistic LAB 300 turntable cartridge alignment tool. That dimension is from the shoulder of the stock headshell to the stylus tip, and may be far different then the one used with the protractor.

Correct cartridge alignment on my Planar Two is assured if I use one of their better cartridges, thanks to their 3 point attachment set-up. Which until their new line came out recently I wasn't interested. This new line might be worth a look for Rega owners, if overpriced.

 

[preacherJohn]

Looking around, there seems to be little information on this. Fluance suggest checking with an alignment protractor. They provide a printable version which looks like a standard Baerwald 1 alignment It looks like you ignore the actual stated overhang and use the alignment protractor.

This is exactly what I did as I didn't understand the stated overhang measurement as it doens't explain where to read the 19.2mm measurement from point to point. I have a printout from my manual which is identical to the plastic protractor I bought on Amazon. The cartridge is aligned to that protractor. Although it's as close as I could get it to the original headshell as I found no measurement from the shoulder of the headshell to the stylus noted.

 

[preacherJohn]

I believe the 19.2mm overhang refers to the distance between the calibration line marked on the protractor to the stylus tip when the line marked "line up with tonearm pivot" is in position That's how it works with the Rega Planar Two I bought last year.

This makes more sense. I never had to set one up like this and always used the other measurement from the headshell shoulder to the stylus. There's many horizontal lines on the protractor with one cross marked with a circle that I would take as where the stylus should rest during the measurement. I don't understand how to make that measurement of 19.2mm? Which points do you measure from?

 

[EWarrior]

Headshell tail to stylus tip distance is one thing. If the turntable manufacturer specifies this distance, it's supposed to be a simple way to reach the correct overhang and offset angle for the stock alignment. It's not overhang itself, just a way to help you find it.

Overhang is the distance by which the effective length arc is larger than the pivot to spindle distance arc.

Most tonearm geometries use two null points to minimize the amount of distortion over the length of a record side. The null points on the Fluance protractor are at 66 and 120.9mm (Löfgren A, aka Baerwald). The cartridge can only align perfectly on both null points at one particular overhang and offset angle. The exact length and angle depends on the pivot to spindle distance.
With Fluance's pivot to spindle distance of 204,8mm, the resulting overhang is 18.6 mm. Löfgren B for IEC groove radii would be closer to 19.2mm

 

[charles 1973]

Nicely explained EWarrior!

John. You should find some lines on the protractor if you look carefully that are probably marked for the correct overhang.

One line wiil be marked "align to tonearm pivot" Do this first.

The grid pattern is used after you set the overhang to the correct distance to square up the cartridge with the arm. Then double check the overhang.

It sounds more difficult then what is is. After some practice it can be done in about the time it took me to text this.

 

[EWarrior]

Nicely explained EWarrior!

John. You should find some lines on the protractor if you look carefully that are probably marked for the correct overhang.

One line wiil be marked "align to tonearm pivot" Do this first.

The grid pattern is used after you set the overhang to the correct distance to square up the cartridge with the arm. Then double check the overhang.

It sounds more difficult then what is is. After some practice it can be done in about the time it took me to text this.

No, these are two point protractors. Nothing to point. Just align the cartridge on one null point, then check on the other. If it's slightly angled on the second null point, the overhang is off.

For pointing, a linear offset protractor is the most comfortable type to use. When used with a piece of string to aim the sightline precisely at the tonerm pivot, these can be pretty accurate.

 

[dankik]

... distance of the Fluance RT-85 overhang on the headshell between the stylus and the rubber washer at the rear of the headshell connector.

RT-85 with Ortofon Blue. Hope this helps.

 

[preacherJohn]

Headshell tail to stylus tip distance is one thing. If the turntable manufacturer specifies this distance, it's supposed to be a simple way to reach the correct overhang and offset angle for the stock alignment. It's not overhang itself, just a way to help you find it.

Overhang is the distance by which the effective length arc is larger than the pivot to spindle distance arc.

Most tonearm geometries use two null points to minimize the amount of distortion over the length of a record side. The null points on the Fluance protractor are at 66 and 120.9mm (Löfgren A, aka Baerwald). The cartridge can only align perfectly on both null points at one particular overhang and offset angle. The exact length and angle depends on the pivot to spindle distance.
With Fluance's pivot to spindle distance of 204,8mm, the resulting overhang is 18.6 mm. Löfgren B for IEC groove radii would be closer to 19.2mm

Thanks for this info; This is the first time I've seen this. It's so common for people to use the shoulder to tip method and I've always did that as the TT manufacturers of my TTs provided this information. This Fluance is the first TT I've ran across that seems to have "rocked my boat" and set the headshell in another way. Many thanks again for this diagram.

 

[preacherJohn]

Thanks to all for your replies; I've learned something new today. As mentioned earlier, the way I learned to set up TTs was with the shoulder to tip method, and a protractor. The overhang provided to me by the manufacturers of the TTs I own always gave that info. And, I've noticed that when people were unaware of their overhang, they would drop a quick note in this forum and someone always provided the standard "49mm" or something similar to the TT that they had. Fluance is the first TT I've bought that does this method of overhang differently. I will study this procedure a little more as soon as I get my sight back in my right eye. Recently I had cataract surgery, and it left my right eye with a detached retina; I had another urgent surgery for this last Friday, and at the moment I am blind in my right eye, with the floaters in my left bad enough I can't focus very well tyring to read. They say 6-8 wks to get my sight back, so I'm presently in Limbo waiting for my results of restoration.

 

[preacherJohn]

Headshell tail to stylus tip distance is one thing. If the turntable manufacturer specifies this distance, it's supposed to be a simple way to reach the correct overhang and offset angle for the stock alignment. It's not overhang itself, just a way to help you find it.

Overhang is the distance by which the effective length arc is larger than the pivot to spindle distance arc.

Most tonearm geometries use two null points to minimize the amount of distortion over the length of a record side. The null points on the Fluance protractor are at 66 and 120.9mm (Löfgren A, aka Baerwald). The cartridge can only align perfectly on both null points at one particular overhang and offset angle. The exact length and angle depends on the pivot to spindle distance.
With Fluance's pivot to spindle distance of 204,8mm, the resulting overhang is 18.6 mm. Löfgren B for IEC groove radii would be closer to 19.2mm

One more question if you don't mind. By looking at this chart, theoretically the overhang tail to tip, would be the same on any cartridge IF the headshell's body were identical in length?

 

[EWarrior]

One more question if you don't mind. By looking at this chart, theoretically the overhang tail to tip, would be the same on any cartridge IF the headshell's body were identical in length?

The length of the headshell body doesn't matter. The slots just need to be long enough to reach the correct distance.

 

[Old Guy8]

Pardon Our Interruption...

This fall, I sprung for one of these alignment fixtures. I've no connection to any of the many Ebay sellers. I don't recall at moment which seller I bought from. But, was stocked in USA. It seemed of good build quality. Aluminum and stainless materials. Choice of Baerwald, Lofgren or Stevenson alignments.

I think it's more precision than my overhang gages. It was faster for me. Set overhang in step 1. And square up cantilever in step 2. Was less frustrating and quicker for me. I would imagine would be even less frustration for straight arms without overhang gages available. I hate going back and forth with a minimal two null point protractor.

I have old eyes and astigmatism. Which makes seeing the stylus difficult. I used the included thumb sized flashlight to see light reflecting off vertical edge of stylus.

If someone aligns carts on more than one table. And has budget.

 

[krautmaster]

This diagram will help you get the overhang really close with just a try or two:

 

[EWarrior]

And don't forget to tape a pencil lead to the front of the cartridge. That will increase the visibility of the error significantly and you have a much better chance of actually finding the correct overhang.

 

[Powertech]

I use a proprietary Ortofon alignment protractor (i use an Ortofon SuperOM30 cartridge) which turns out to be Baerwald1. It has the 2 setting points as listed above, and it has the same error information marks for moving the cartridge forwards or backwards to correct the error.

I suspect that if you align your cartridge correctly with the supplied protractor the overhang will 'magically' match the Fluance requirement.